Propulsion control system for self-propelled two-car trains

ABSTRACT

A special signal is transmitted through train line communication channels from a transmitter means on one car to a receiver means on the other car of the self-propelled train unit. The transmission of this signal is controlled by the propulsion control logic means located on one car. The receiver means includes a relay which controls the propulsion condition of one of the cars, normally the trailing car, shifting between direct, multiple unit control from the operator&#39;&#39;s position and a preset condition, e.g., propulsion off, as the special signal is or is not received. The special signal may be direct current energy or alternating current energy having a selected frequency characteristic. This latter signal is superimposed on train line channels used for other purposes, e.g., the directional train line wires. The direct current signal, however, requires a separate, dedicated train line channel used in conjunction with the directional train line wires.

United States Patent [151 3,698,325 Grundy 1 Oct. 17, 1972 [54] PROPULSION CONTROL SYSTEM FOR [57] ABSTRACT SELF-PROPELLED TWO-CAR TRAINS [72] Inventor: Reed H. Grundy, Murraysville, Pa.

[73] Assignee: Westinghouse Air Brake Company,

Swissvale, Pa.

[22] Filed: Aug. 26, 1970 {21 Appl. No.: 66,97l

[52] US. Cl ..l05/61 [51] Int. Cl ..B6lc 3/00 [58] Field of Search 1 05/61 [56] References Cited UNITED STATES PATENTS 3,482,089 12/1969 Raffel et al. ..105/6l X Primary Examiner--Arthur L. La Point Assistant Examiner-George H. Libman Attorney-H. A. Williamson, A. G. Williamson, Jr. and JpB. Sotak A special signal is transmitted through train line communication channels from a transmitter means on one car to a receiver means on the other car of the selfpropelled train unit. The transmission of this signal is controlled by the propulsion control logic means located on one car. The receiver means includes a relay which controls the propulsion condition of one of the cars, normally the trailing car, shifting between direct, multiple unit control from the operators position and 'a preset condition, e.g., propulsion off, as the special signal is or is not received. The special signal may be direct current energy or alternating current energy having a selected frequency characteristic. This latter signal is superimposed on train line channels used for other purposes, e.g., the directional train line wires. The direct current signal, however, requires a separate, dedicated train line channel used in conjunction with the directional train line wires.

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PROPULSION CONTROL SYSTEM FOR SELF- PROPELLED TWO-CAR TRAINS My invention relates to a propulsion control system for self-propelled, two-car train units. More specifically, this invention deals with a control system using train line wires as communication channels for transmitting function control signals between the cars in a self-propelled, multiple unit train comprised of one or more two-car operating units.

It is conventional to control the motors and brakes on various car units of self-propelled, multiple unit trains by direct signals transmitted over different train line wires from a controller device at the operators position. Such train line wires extend along the train from car to car, normally in the form of a cable, with couplers connecting the wires automatically between the cars as the car units are assembled into a complete train. In such basic control arrangements, the apparatus on each car responds in an identical manner to each different signal transmitted from the control location of the train over the train line wires. More sophisticated control systems are also known whereby different controls are applied to each car of a multiple unit train or a particular propulsion or braking control is applied at different times to the various cars. In such an arrangement, the variable controls or different methods of operation are selected by the train operator. Such sophisticated systems require extra equipment in order to transmit and receive the special controls or the special patterns of identical controls. A specific car arrangement now frequently used for selfpropelled trains, especially in rapid transit systems for off-peak operation, is a semi-permanently coupled pair of cars having operators control locations only at the outside ends of such units, that is, one on each car. These two cars operate as a unit even when coupled into longer trains, since certain equipment is usually shared, and are known in the art as a married pair of cars. The previously mentioned highly sophisticated control systems used with multi-car trains composed of individual car units can not be efficiently or effectively used on such two-car, married pair train units. Yet the efficient operation of such two-car units frequently requires more than a direct signal, propulsion control arrangement with identical control functions always simultaneously effective on each car. In other words, a system of variable controls is needed that does not require a great variety of control patterns. Such optional controls for the two cars of the unit may also provide sufficient variety of operational modes for multiunit trains comprising several coupled pairs of such cars.

Accordingly, an object of my invention is an improved propulsion control system for a self-propelled train comprising a married pair of cars.

Another object of the invention is a control function communication system for transmitting operating controls over train line channels also in use for other purposes to provide a more selective operation of the car units of self-propelled trains.

A further object of the invention is a propulsion control system for a married pair of self-propelled railroad cars utilizing special control signals transmitted over train line channels to selectively establish different operating controls on each car ofa pair.

It is also an object of the invention to provide a communication arrangement for transmitting control functions between the cars of a married pair train unit to establish different operating modes on each car as desirable for optimum operation of the train.

Yet another object of the invention is an operational control system for a pair of self-propelled railroad cars in which a special characteristic signal is selectively applied, from a transmitting unit at a location on one of the two cars, over train line communication channels and received by a responsive receiver unit on the other car to modify the operational function control otherwise exercised over the regular signal channels.

Other objects, features, and advantages of this inven tion will become evident from the following specification when taken in connection with the accompanying drawings and the appended claims.

In practicing my invention, a signal transmitter means is provided on one car of a married pair train unit together with an associated receiver means, usually located on the trailing car. In one species, a set of associated transmitter and receiver means is provided for each direction of train operation. In this arrangement, the active transmitter, selected in accordance with the direction of train movement, is on the leading car and the associated receiver means is located on the following or trail car. In each form, the transmitter develops or originates a special signal which is, as specifically shown, normally transmitted over a selected train line communication channel. However, an arrangement using a normally off special signal is also shown. Depending upon the specific signal characteristic, the communication channel is separate from others in use or the signal is superimposed on a channel also used for conventional control signals. In one specific case, the special signal is a direct current voltage applied to a separate and dedicated train line channel. In other species of the invention, the signal is an alternating current, of a preselected frequency, which is superimposed on the regular directional train lines. In all of the species specifically illustrated, the receiver means includes a control relay which responds to the presence or absence of the special signal. This relay controls the propulsion functions on that particular car of the pair, normally conditioning them when the signal is present to follow the direct control established by the train operator. When the signal is absent, the relay interrupts the direct controls and shifts the car propulsion means to a preset condition, for example, to a propulsion-off condition. In the species incorporating a normally off special signal, the conditioning of the car propulsion functions in response to the relay operation is reversed. Where the special signal has a special characteristic, that :is, is an alternating current s'ignalrsuperimposed on a directional train line, the receiver means includes some means of rectification so that a direct current relay may function as the control relay on each car. In each of the forms, the transmission of the special signal is controlled by a propulsion control logic means which is responsive to speed, acceleration, and other factors to establish an optimum operating condition for the train unit.

I shall now describe in greater detail four arrangements embodying the features of my invention and then point out the novel features thereof in the appended claims. In describing the different arrangements, reference will be made to the accompanying drawings in which:

FIG. 1 illustrates the control system embodying a first form of the invention using a separate train line communication channel for the special signal.

FIG. 2 shows a second form of the control system embodying the invention in which the special signal has a distinct characteristic and is superimposed on train line channels used also for other purposes.

FIG. 3 shows a modification of the form illustrated in FIG. 2.

Another modification of the FIG. 2 species is illustrated in FIG. 4.

In each of the drawings, similar reference characters refer to similar parts of the apparatus.

Referring now to FIG. 1, the two conventional dotdash blocks represent the individual cars of the two-car train unit, car 1 on the left and car 2 on the right. As previously described, these two cars are semi-permanently coupled to form a so-called married pair unit. This two car unit is always operated as a train unit, either by itself or coupled with similar units to form a longer train. The train unit has an operators control location on each outer end in order to provide for two direction operation. It may be noted that even though this unit, illustrated as a single two-car unit, is coupled at times with similar units to form a multi-car train, such use does not change the basic operation of the system of my invention as will be appreciated, from the following description, by those having knowledge and skill in the particular art.

The two cars are also joined by train line wires extending along the length of the train unit. In FIG. 1, only three wires are shown in each car, designated as lines 1, 2, and Y, which are part of a large number of such wires normally forming a train line cable. When the two cars are mechanically coupled, associated train line wires in each car are automatically electrically connected between the cars by a coupler unit. These connections are shown by conventional symbols between the illustrated car blocks. It will be noted that train line 1 in each car is coupled to train line 2 in the other car, for purposes described shortly. Also shown at various points in the illustrated circuit arrangements are connections to a common train ground wire or train ground base level. These connections are illustrated by conventional grounding symbols used in the art. It is to be understood that the same ground level base exists on each car of the two-car train unit or in even longer trains.

A car battery CB is shown in each car to conventionally provide a source of direct current energy for the operation, not only of the illustrated arrangement of my invention, but also of all other apparatus associated with train operation. Each battery CB is shown with its negative terminal connected to the train ground and the positive terminal connected to train lines and/or other apparatus through switches which will be described later. In the specific illustration in FIG. 1 and in the other figures of the drawings, two batteries CB are shown, one for each car. It will be understood, however, by those working in the art that the train unit, that is, the married pair, may have a single car battery of sufficient capacity to provide for all energy used on both cars. If a single battery is provided, the positive energy terminal is supplied to the other car through a particular train line wire so that, whether one or two batteries are used, a connection to the positive terminal of the direct current energy source for the train is available on each car.

The train line wires 1 and 2 are defined as the directional train line wires, one or the other of which on each car is energized to establish the direction of train movement for all of the apparatus on the train. In FIG. 1, and the other figures also, energy is directly applied from battery CB to train line 1 on a car when the train is to move with that car leading and the other car trailing. Since each line 1 is cross connected to line 2 on the other car of the pair, the application of energy to a line 1 also energizes the associated line 2 on the paired car. It may be noted that similar cross connections are made to the directional train line wires on other car pairs which may be coupled to form a longer train.

Each directional train line 1 may be connected to the positive terminal of the corresponding battery CB over a normally open contact of a switch shown, for convenience, as a stick type pushbutton device, as illustrated by the conventional symbol for such type pushbuttons used in the drawings. Other types of manually operated switches providing equivalent circuit operation may, of course, be used in the system. For example, on car 1, the lead car switch LCSl, when actuated, closes its movable contact armature against the corresponding fixed contact point and holds this circuit closed when the actuating pressure is removed. Switch LCSl must then be pulled to open the contact to interrupt the circuit closed therethrough. When the train operator actuates switch LCSl, positive direct current energy from battery CB is applied over the contact of this switch to train line 1 on that car and to train line 2 on the other car. This actuates the conventional apparatus connected between these directional train lines and the ground terminal to establish train direction to the left so that car 1 is leading and car 2 is trailing. Obviously this establishes the operators position in car 1 as the control location for train movement. In a similar manner, the actuation of switch LCS2 in car 2 applies, over its contact, positive direct current energy to its train line 1 and thus to train line 2 on car 1. This establishes train direction to the right so that car 2 leads and car 1 trails. In this condition, the operators position in car 2 is the controlling location for the train. Switches LCSl and LCS2 are so arranged that only one may have its contact closed at a particular time. This interlock may be accomplished by any means or manner known in the associated art and it is not necessary to here show the details of such arrangements. It is sufficient to understand that if the contact of switch LCSl is closed, the corresponding contact of switch LCS2 must be open, and vice-versa. It is to be noted also that only switch LCS on the lead car is actuated if two or more married pairs are coupled into a longer train.

In this first form of my invention, a separate train line Y is used to transmit the special propulsion function control signal which provides additional selection in the operating modes or conditions for controlling the movement of this train unit. Since this special signal is specifically the presence or the absence of direct current energy on line Y, a transmission channel separate from the train lines used for normal control functions is required. The train line Y is coupled between adjacent cars to provide a continuous channel throughout the train unit to include other pairs of cars if a longer train has been assembled.

The transmitter means comprises a connection from the positive terminal of battery CB in car 1 and a normally closed contact XA. As designated, contact XA is controlled by a propulsion control logic means or apparatus which is responsive to train speed, acceleration, load or weight, and other associated movement factors to establish the propulsion power required to obtain optimum train operation within the speed or acceleration setting made by the train operator at his control position. One form of such apparatus is disclosed in the copending application for Letters Patent of the United States Pat. No. 21,594, filed Mar. 23, 1970 by George W. Donaldson for a Car Propulsion Scheme Utilizing Married Pairs of Propulsion Units, which application has the same assignee as this present case and has issued as U.S. Pat. No. 3,656,037, dated Apr. 11, 1972. Specifically, contact XA may be a contact of a relay such as a relay X, which is controlled over a wire 167 by the propulsion control logic unit 95, as shown in FIGS. 5 and 4, respectively, of the Donaldson application. In other words, the relay controlling contact XA is normally energized when the train is in operation and the logic means has determined that all propulsion power apparatus should be in the on or operating condition. In the present arrangement, however, contact XA is preferably located, as is shown, on the same car of the pair as the propulsion control logic means. It is to be understood, however, that contact XA otherwise represents a circuit closure by or through the unit 95 shown in the Donaldson application and need not be a single relay or other type contact. That is, contact XA herein represents a circuit which may be open or closed by the propulsion control logic element in accordance with its determination of the required amount of propulsion power needed for optimum train operation.

When contact XA is closed, it applies positive direct current energy from battery CB to train line Y which represents a first condition or mode of train operation. When the propulsion control logic determines that less than the full propulsion power will provide optimum operation of the train, contact XA is opened and removes energy from train line Y, this being a second condition or mode of operation for the train. In the first condition, the special function control signal thus is the transmission of positive direct current energy over train line Y to condition the propulsion means to respond to the operator's control. For the other condition, the special signal is the absence of energy on train line Y, which reduces the total propulsion power that is subject to the operators control.

Each car is supplied with a car control relay CC for receiving the special function control signal. This relay is designated as relay CCl on car 1 and as relay CCZ on car 2. Each is, in this first form, a two winding, direct current neutral relay. Energy applied to either winding actuates the relay so that it picks up to close its front contacts. The lower winding of each relay CC is connected between train line Y and the ground terminal while each upper winding is connected between train line 1 of that car and ground. It will thus be obvious that a relay CC picks up if positive energy is applied to the corresponding train line 1 or to train line Y.

To conventionally illustrate the control exercised by a relay CC on the propulsion function of the corresponding car, a partial circuit network controlled by contacts of the relay is shown for each car. When a relay CC is picked up, the normal car propulsion controls are made effective so that the car responds to the multiple unit controls manually selected by the train operator at his control position and transmitted over other train lines not shown. When both relays CCl and CC2 are picked up, the propulsion functions on each car are controlled in an identical manner by the operator. Conversely, when a relay CC is released, a preselected fixed control condition for that particular car, shown as being propulsion controls disconnected and thus the propulsion power off, is made effective independent of any direct controls selected by the train operator. It is emphasized that this conventional showing of the shifting of the car propulsion controls, between a first and asecond operating condition, by relay CC is by way of example only and is not intended to illustrate actual car control circuits. Rather, the conventional showing illustrates that, when the front contacts of a relay CC are closed, propulsion apparatus on the corresponding car is controlled by direct signals over other train line wires, as established by the operator at his control position. When these contacts are open, the car apparatus is independent of the operators control. This allows a separation of the propulsion controls of the two cars of the married pair unit so that a larger selection of propulsion control'conditions may be available to the train operator.

It is intended in this application, where operator control is mentioned, to include in that term the automatic operation of the train unit without operator intervention. Such ATO systems are known and the substitution of such systems, to include direction of movement selection, for the manual operator control herein described will be evident to those skilled in the art. Such substitution will not affect either the operation or novelty of the various disclosed arrangements of my invention.

Describing the operation of the form of the invention illustrated in FIG. 1, it is assumed that the two-car train unit is to move with car 1 in the lead position. In order to establish this condition, the train operator actuates switch LCSl to close its contact and thus apply positive direct current energy from car battery CB to train line 1 on car 1. As soon as the train is readied for operation, i.e., switch LCSl is actuated, the propulsion control logic is actuated and closes contact XA. This applies positive energy from battery CB to train line Y. Thus both relays CCl and CC2 are energized and each relay picks up to close its front contacts to establish direct multiply unit control of the corresponding car propulsion apparatus from the operators position. The fact that both windings of relay CCl are presently energized is immaterial to the operation of the overall system. However, it should be noted that the contact of switch LCS2 is open at this time so that no energy is applied to train line 1 on car 2. The train may now be moved with both cars operating in multiple under the direct control of the operator from his position in lead car 1.

As long as the control functions selected, i.e., the operation desired, by the operator are best satisfied by the full use of the propulsion apparatus on both cars, the propulsion control logic holds contact XA closed. When the train operating factors are such that partial operator control is sufficient to obtain the desired operation, contact XA is opened to establish the second operating mode or condition. This deenergizes train line Y and relay CC2, since only its lower winding was energized, releases. Relay CCl, of course, is held energized by the application of direct current energy to its upper winding. The release of relay CC2, to open its front contacts, shifts car 2 to a no-propulsion condition and this car remains in such operating mode while relay CC2 remains released. This action is accomplished by the interruption of the transmission of the special signal over train line Y, that is, over the train line communication channels. This interruption of the special signal is actuated by the transmitter means, specifically contact XA, and, through the response of the receiver means comprising relay CC2, effects the desired separation of the propulsion controls for each car of the train. It will be obvious that, if car 2 is the lead car, relay CC2 will remain energized when contact XA opens and relay CCl will release. This disconnects the control of the propulsion apparatus on car 1 from the operator's position and establishes the second operational mode on car 1.

Referring now to FIG. 2 showing a second form of the invention, each of the two cars illustrated by the conventional blocks in provided with a switch LCS, again shown as stick type pushbuttons. The positive terminal of each car battery CB is connected as before over the contact of the associated switch LCS to train line 1 on that car. Each car is further supplied with a control relay CC having, in this form, only a single winding. The contacts of the relay control the car propulsion circuits in the same manner as described for FIG. 1. The winding of each relay is connected to train line 1 on that car through a single diode.

Each car is further provided with an oscillator unit which supplies the special control signal having, in this form, a preselected frequency characteristic. This special signal may be an audio tone signal but preferably the frequency is at a higher level. Each oscillator is shown by a conventional triangular block, designated OSC, since any type of oscillator circuit known in the corresponding art, although preferably of a solid state design, is usable. The output of the oscillator on car 1 is supplied over contact XA, which is the same as the similarly referenced contact in FIG. 1, to train line 2 on that car and thence through the coupling to train line 1 on car 2 and through the diode to relay CC2. However, to avoid requiring a second propulsion control logic means, i.e., one one each car, the output of the oscillatoron car 2 is transmitted over a separate train line Y to car 1. On car 1, this alternating current signal is connected over contact XB, which is controlled by the propulsion control logic in a manner similar to contact XA, to train line 1 on car 1 and thence from that train line, or directly, through the diode to relay CCl. Thus the propulsion control logic means on car 1 functions to control the transmission of the special signal from the active oscillator to set up the desired operating mode of the train. It is to be noted, however, that since the output of the oscillators is an alternating current of a preselected frequency, train line Y may actually be a train line also used for a direct current, multiple-unit control signal, other than directional control signals, with the alternating current signal being superimposed thereon. If this alternate arrangement is used, the oscillator output is coupled, through a filter unit, on car 2 to train line Y and on car 1 from train line Y to contact XB. It is also to be noted that, in this form, the special control function signal, having an alternating current frequency characteristic, is superimposed upon the directional train lines for transmission from one car to the other. This is accomplished without interference with the normal use of these train line wires 1 and 2 for direction selection for the train. For each car, the oscillator unit and the associated contact X comprise the transmitter means controlling the special signal transmission.

Assuming again that car 1 will be the lead car of the train, the operator actuates switch LCSl to apply direct current positive energy to train line 1. Relay CCl in car 1 is energized through the circuit extending from train line 1 through the diode and the relay winding to the ground terminal. The diode, of course, performs no rectification under these conditions as direct current energy is being supplied. With front contacts of relay CCl closed, car 1 is therefore under direct control of the train operator. The oscillator unit on car 1 is also energized since its input is connected across train line 1 and the ground terminal, the latter connection shown in a conventional manner to illustrate the general connection of the oscillator unit to the train ground level. The output of the oscillator on car 1 is fed over the normally closed contact XA and train line 2 to train line 1, car 2. This alternating current signal, half-wave rectified by the diode on car 2, energizes relay CC2 which is connected by that diode to train line 1. The circuit, of course, also includes the ground connection of the oscillator and the ground connection from the other terminal of the relay winding so that the circuit is actually completed through the train ground circuit connection. It is to be noted that the relays CC may be of an alternating current type which also respond to direct current energy but preferably they are a direct current type and the circuits include diodes as shown in FIG. 2. With both car control relays picked up, each cars propulsion apparatus is controlled directly by the train operator.

When the propulsion control logic determines that a shift to the second operational mode is in order, contacts XA and XB open, although the latter has no effect at this time. Contact XA interrupts the supply of energizing current for relay CC2, specifically by opening the connection from the oscillator output to train line 2. Release of Relay CC2 shifts the control elements in car 2 to the predetermined second condition so that, as previously described, this car remains in a no-propulsion condition while the operator varies the movement of the train through his remaining control of the functions on car 1. It will be noted that during the assumed situation, there is no direct current energy on train line 1, car 2, which will cause the operation of the oscillator unit on car 2. If car 2 is the lead car, the operation under control of switch LCS 2 and contact XB will be obvious with reference to the drawing and the immediately preceding description.

Referring now to FIG. 3, there is illustrated a modification of the FIG. 2 system in which only one transmitter means, shown specifically in car 1, and one receiver means, included in the apparatus in car 2, are required. Each car again has a car battery CB and a leading car switch LCS, switch LCSl having two contacts. However, only two train line communication channels are required, comprising the directional train line wires 1 and 2. On each car, depending upon the selected direction for train movement, energy from the positive terminal of the car battery is selectively applied to the corresponding directional train line 1 over contact a of the associated switch LCS. The transmitter means includes an oscillator unit on car 1 of the same type previously described and contact XA. It will be obvious that direct current energy is supplied to the oscillator unit over the normally closed contact XA from battery CB of car 1. Contact b of switch LCSl is required to channel the oscillator output to directional train line 1 or directional train line 2, depending upon which car is the lead car of the train.

In this particular form of the invention, the receiver means, shown in car 2, comprises a full-wave rectifier element Z and an associated capacitor unit C as well as car control relay CC2, which again is a single winding, direct current relay. The input terminals of the fullwave bridge rectifier Z are connected in series with capacitor C across train lines 1 and 2 with control relay CC2 being connected across the output terminals of the rectifier. It will become obvious that the receiving means could be mounted and connected in the same fashion between the directional train lines on the same car on which the oscillator unit is located. As shown, this arrangement is particularly adapted for use in systems where the married pair units are normally operated with car 1 leading or where a complete operators position is only provided in car 1, with the car 2 control position being provided for hostler use only.

Describing the operation of the system of FIG. 3, it is again assumed that car 1 is selected to be the lead car in the train movement. The train operator, therefore, actuates switch LCSl to close its two normally open contacts which, of course, applies direct current energy from car battery CB to directional train line 1 on that car so that the apparatus on each car associated with train movement is energized. When the train unit is thus activated, direct current energy is applied over contact XA to the oscillator which is also connected to ground. The outputof the oscillator is then applied over normally open or upper fixed contact b of switch LCS], now closed, to train line 2 on car 1. The oscillator alternating current output of the preselected frequency thus flows through capacitor C and bridge rectifier Z between train lines 1 and 2 on car 2, thence over contact a of switch LCSl and through battery CB to the ground terminal, returning from this terminal through the train ground to the oscillator unit. If necessary because of high internal alternating current im pedance of the battery, a capacitor shunt may be used. The flow of the alternating current through rectifier Z causes a direct current voltage to appear at the rectifier output which energizes the winding of relay CC2 so that it picks up to close its front contacts. This establishes a normal car propulsion control for car 2, which is a direct multiple unit type control from the train operators position with the control functions following identically those exercised on car 1.

When the propulsion control logic means determines that control of train movement by only the propulsion apparatus on car 1 will be sufficient, contact XA opens which interrupts the supply of direct current energy to the oscillator unit. This cuts off the oscillator output which thus supplies no alternating current energy to the bridge rectifier. This in turn interrupts the direct current supply to relay CC2 which, thus deenergized, releases. The opening of its front contacts interrupts the control of the car 2 apparatus, i.e., places it in a nopropulsion condition.

If car 2 is to be the leading car of the train, the operation of switch LCS2 supplies direct current energy to train line 1, car 2. This energy on line 2, car 1 actuates the car movement control apparatus on car 1 to respond to direct controls from the operators position on car 2. The activating of the car 1 control apparatus causes the propulsion control logic to close contact XA which supplies direct current energy to the oscillator unit in car 1. Once again the output of the oscillator is applied to the capacitor, rectifier circuit connected between train lines 2 and l on car 2, the circuit being traced from the oscillator output over the normally closed or lower fixed contact b of switch LCSl to train line 1 on car 1, through rectifier Z and capacitor C to train line 1, car 2, and thence over contact a of switch LCS2 and through battery CB of car 2 to the ground terminal, returning to the oscillator unit through the train ground connections. Relay CC2 is energized under this condition so that its front contacts are closed and the control of car 2 propulsion apparatus is directly from the operators control position in car 2. The selection of a separated condition for the propulsion controls of car 2 is still controlled by the opening of contact XA, by the propulsion control logic means, which interrupts the supply of direct current to the oscillator. This shuts off the alternating current output and causes the release of relay CC2 in the manner previously described.

A second modification of the arrangement of FIG. 2 is disclosed in FIG. 4. This arrangement uses the fullwave rectifier, capacitor type receiver of FIG. 3 but provides such a receiver unit including a relay CC for each car of the pair. Further distinguishing from the FIG. 3 arrangement, each rectifier, capacitor series circuit is connected between train line 1 on the associated car and the ground terminal connection. The single transmitter means comprises an oscillator, of the same type as previously described, and contact XA, controlled by the propulsion control logic means. It is to be noted, as will be shortly described, that the operation of the apparatus is inverted from that of the prior arrangements. In other words, the special control function signal is transmitted when it is desired to separate or interrupt the control of the trail car and control the movement of the train only by the propulsion apparatus on the lead car. Contact XA is therefore normally open. Further, each relay CC connects the normal propulsion controls for the corresponding car to the operators control position over back contacts of the relay rather than the front contacts used in the other arrangements. Thus when the special signal is received and actuates a particular relay CC, that relay picks up to interrupt the propulsion control circuit by opening its back contacts.

As before, each car is provided with a battery CB and the direct current energy from that battery is applied to the corresponding train line 1 over the contact of the lead car switch LCS. However, in lieu of shifting the oscillator output over a contact of switch LCSl, the FIG. 4 arrangement adds on car 1 a direction relay DR which is connected between train line 1 and the ground terminal. Thus when switch LCSl is actuated to apply energy from battery CB to train line 1 on car 1, relay DR picks up to close its front contact a. It will be noted that the closing of this front contact connects the output terminal of the oscillator to train line 2 on car 1 whereas if relay DR is released so that its back contact a is closed, the oscillator output terminal is connected to the corresponding train line 1.

Briefly describing the operation of this final arrangement, if car 1 is to lead the train movement, switch LCSl is actuated to apply positive direct current energy to train line 1 on car 1 and thus to train line 2 on car 2. This actuates the propulsion controls on both cars to respond to the controller in the operators position on car 1. In addition, relay DR is energized and picks up to close its front contact a, thus connecting the oscillator output terminal to train line 2 on car 1. The propulsion control logic means is actuated so that it will respond to the train movement performance but in this arrangement does not close contact XA at this time. With contact XA remaining open, the oscillator remains deenergized so that it produces no output for application to the train line. Since, in this species, back contacts of each relay CC normally activate the car propulsion controls, i. e., connect them to the operators position over train lines, there is no need to energize either relay CC with energy from the directional train lines.

The train then moves under the control of the operator, both cars responding in multiple unit fashion to to his selected controls transmitted to the propulsion apparatus on each car. When the propulsion control logic means determines that single car propulsion power is sufficient to provide the desired operation, contact XA is closed. This energizes the oscillator unit and its out put is applied to line 2 in car 1 and thus to train line 1 in car 2. The flow of this alternating current of the preselected frequency through capacitor C2 and rectifier Z2 to the ground terminal, returning through the train ground connection to the oscillator unit, produces a direct current output from rectifier Z2. This direct current energy is applied to the winding of relay CC2 which, thus energized, picks up to open its back contacts. This interrupts the propulsion control for car 2 and establishes a second mode of operation in the train unit, that is, with car 1 propulsion on and car 2 propulsion off. If the propulsion control logic later determines that driving power from the propulsion apparatus for both cars is needed for proper operation, contact XA is opened to turn off the oscillator. With no output from rectifier Z2, relay CC2 then releases and restores the control of the car 2 propulsion apparatus to the operators position. It will be also noted that if the oscillator should fail or another fault condition occur so that relay CC2 is no longer energized, the release of this relay will restore the full control of both cars to the operators position. While this may not provide optimum operation of the train, at least, under the fault conditions, the operator will have full control of both cars to control the movement of the train and there will be no hindrance to the train movement because of the fault.

If car 2 is to be the leading car, switch LCS2 is actuated to provide direct current energy to train line 1 in car 2 and thus to train line 2 in car 1. While this ac tivates the propulsion apparatus on both cars to respond to controls from the operator's position in car 2, relay DR is not energized and remains in its released position. The propulsion control logic means, however, is activated to respond to the train movement performance and operates contact XA as is appropriate. When contact XA is closed so that an oscillator output is produced, this output is applied to train line 1 car 1, and thus to the receiver unit including capacitor C1 and rectifier Z1. The output from rectifier Z1 energizes relay CCl and this relay picks up to interrupt the control of the car 1 propulsion apparatus from the operators position. In other words, the trailing car in the present movement direction is shifted to a mode 2 type of operation, that is, no propulsion control. Said in another way, in the arrangement shown in FIG. 4, regardless of the direction of the train movement, when single car propulsion operation is established, it is the propulsion apparatus on the lead car that remains responsive to the operator's control, which is a preferable type of operation.

It will be understood, in connection with the description of the operation of the FIG. 4 arrangement, that, when other married pair units are coupled to that shown to form longer trains, the propulsion control apparatus on these other units function in an identical manner under control of the transmitter on the illustrated car 1. In other words, when car 1 is the lead car of the train, the transmission of the control signal from the oscillator on the illustrated car 1 when contact XA closes energizes relay CC2 on the trailing car of each pair to cut off the propulsion power on those cars. If the train is so formed that the illustrated car 2 is the lead car, the transmitter means on the illustrated car 1 still controls. The transmission of the signal will energize the relay CCl on each pair to cut off the power on those cars. Similar operation will occur in a longer train if the other disclosed arrangements are used, in keeping with the typical operation of each species. For example, in the FIG. 3 arrangement, it will alwaysbe the propulsion apparatus on car 2 in each pair that is cut off when the special control signal is absent.

It will be obvious that the actual propulsion control on car 2 in the FIG. 3 arrangement may also be inverted, as in FIG. 4, if desired. In this alternative, the special signal is transmitted from the car 1 oscillator only when the propulsion power on car 2 is to be turned off. Such inverted control is not possible in the other two species. Further, a combination of the single oscillator transmitter circuitry of FIG. 3 with a single diode, relay type receiver on each car, connected to the directional train lines as in FIG. 2, provides another alternate arrangement which may be preferred for some installations.

The arrangement of my invention thus provides an effective and efficient means for improving the propulsion control of a married pair train unit without requiring elaborate apparatus by which the additional propulsion control functions are executed. In other words, an additional operating condition may be established beyond the execution of simultaneous and identical controls on each car directly controlled from the operators position. The arrangement of the invention allows a selection of the control of the propulsion elements on only a single car with the other car operating in a propulsion power off condition. These results are obtained with simple transmitter and receiver combinations. lf extra train line wires are available, the transmitter may be a simple switch which applies direct current energy to the extra train line. If it is desired to eliminate the use of an extra train line, the transmitter adds at most only a simple oscillator unit on each car with the receiver means requiring a relay and a diode or rectifier element. These requirements may be reduced, if desired, to only a single oscillator unit with the receiver utilizing a fullwave rectifier and capacitor element. If it is desirable that the propulsion power of the selected lead car always be used, with the selective power off condition established as appropriate on the trail car, only a single oscillator transmitter need be used with a receiver unit on each car. In each case, an efficient and effective selective control arrangement for two-car train units is provided.

Although I have herein shown and specifically described but four forms of propulsion control arrangements embodying the features of my invention, it is to be understood that various other modifications may be made therein within the scope of the appended claims without departing from the spirit and scope of my invention.

Having thus described my invention, what I claim is:

l. A propulsion control system for self-propelled railroad cars operating in married pair formation, each car having separate propulsion means, comprising in combination,

a. a plurality of communication channels extending between the two cars .of said pair and including at least a pair of directional train lines alternately ac tivated in accordance with the selected direction of movement of said car pair to establish selective operator control of both car propulsion means,

. a propulsion control logic means on one car of said pair jointly responsive to the activation of either directional train line and to predetermined operating factors during movement of said car pair for determining the optimum mode of a first and a second predetermined operating mode of said car pair, I

. a selector means on each car coupled to said communication channels and operable for activating a selected one of said directional train lines to establish the corresponding car as the lead car and the remaining car as the trail car for a desired direction of movement,

d. a transmitter means on said one car coupled to said communication channels for at times transmitting a control signal to said other car,

e. a receiver means on said other car coupled to said communication channels for receiving said control signal when transmitted,

f. a switching means controlled by said control logic means for selecting between said first and said second operating modes in accordance with the determined optimum mode,

. said switching means coupled to said transmitter means for actuating the transmission of said control signal when said first operating mode is selected and for interrupting the control signal transmission when said second operating mode is selected,

. said receiver means also coupled to the propulsion means on said other car and responsive to said control signal for selectively actuating said other car propulsion means to a first or a second operating condition as said control signal is transmitted or interrupted, respectively.

2. A control system as defined in claim 1 in which said first operating mode comprises the propulsion' means of both cars of said pair conditioned to operate under multiple unit control by the operator of the train including said pair of cars and said second operating mode comprises the propulsion means of a single car only conditioned to operate under said operators control, the second car propulsion means being in a preset condition.

3. A control system as defined in claim 2 in which,

a. said transmitter means further includes an oscillator for supplying when activated an alternating current control signal having a preselected frequency characteristic,

b. said switching means is connected for activating said oscillator only when said first operating mode is selected,

c. said receiver means comprises,

l. a relay for shifting said other car propulsion means between its multiple unit and preset operating conditions as said relay is energized and deenergized, respectively, and

2. rectification means fro coupling said relay to said channels to be energized when said alternating current signal is present.

. A control system as defined in claim 2 in which,

a. said transmitter means further includes a source of direct current energy for supplying said control signal,

. said switching means connects said source to said communication channels only when said first operating mode is selected, and

c. said receiver means comprises a relay responsive to direct current energy and coupled to said channels and the corresponding propulsion means for shifting said propulsion means between its multiple unit and preset operating conditions as said source is, respectively, connected to or disconnected from said channels.

S. A control system as defined in claim 1 in which,

a. said transmitter means further includes an oscillator for supplying when activated an alternating current control signal having a preselected frequency characteristic,

b. said switching means is coupled for at times activating said oscillator in accordance with the selected operating mode for said cars, and

c. said receiver means comprises,

1. a relay coupled for shifting the other car propulsion means between its two operating conditions as said signal is received or absent, and

2. rectification means for coupling said relay to said channels to respond to said alternating current control signal when transmitted.

6. A control system as defined in claim in which said combination further includes,

a. a receiver means on each car including,

1. a relay coupled for shifting the corresponding propulsion means between its two operating conditions as the control signal is or is not received by that receiver means,

2. a rectification network for coupling the associated relay to a preselected one of said channels, different for each car, to respond at times to said control signal,

b. a directional relay coupled to said channels and responsive to the selection of a lead car by said selector means for coupling said transmitter means to the preselectedchannel to which the receiver relay on the trail car is coupled by its associated rectification network.

7. A control system as defined in claim 1 in which,

a. said transmitter means includes a direct current energy source and said switching means,

1. said source coupled by said switching means to a third communication channel distinct from said directional train lines for transmitting direct current energy as said control signal when said first operating mode is selected,

b. a receiver means is provided on each car,

0. each receiver means comprises a relay coupled to receive operating energy at times from said third channel and at other times from the directional train line activated when the corresponding car is established as the lead car,

1. each relay also coupled for shifting the associated propulsion means between its first and second operating conditions as said relay is energized and deenergized, respectively.

8. A control system as defined in claim 1 in which,

a. said transmitter means includes an oscillator for transmitting, when actuated by said switching means, an alternating current control signal having a preselected frequency characteristic,

1. said oscillator coupled to the second or first directional train line as said one car is established as the lead car or trail car, respectively,

b. said receiver means comprises a full-wave rectifier means and a relay,

1. the rectifier input being coupled between said directional train lines for receiving said alternating current control signal when transmitted,

2. said relay coupled to the rectifier output for receiving energy when said control signal is received,

c. said relay further coupled for actuating the propulsion means of said other car to its first and second operating conditions as said relay is energized and deenergized, respectively.

9. A control system as defined in claim 1 in which,

a. said transmitter means includes an oscillator for transmitting, when actuated by said switching means, an alternating current control signal having a preselected frequency characteristic, 1. said oscillator coupled to the second or first directional train line as said one car is established as the lead car or trail car, respectively,

b. a receiver means is provided on each car of said pair,

c. each receiver means comprises a full-wave rectifier means and a relay,

1. the rectifier input being coupled to the directional train line non-activated when the corresponding car is established as the trail car for receiving said alternating current control signal when transmitted on that train line,

2. said relay coupled to the rectifier output for receiving energy when said control signal is received,

d. said relay further coupled for actuating the propulsion control means of the corresponding car to its first and second operating conditions as said relay is energized and deenergized, respectively. 

1. A propulsion control system for self-propelled railroad cars operating in married pair formation, each car having separate propulsion means, comprising in combination, a. a plurality of communication channels extending between the two cars of said pair and including at least a pair of directional train lines alternately activated in accordance with the selected direction of movement of said car pair to establish selective operator control of both car propulsion means, b. a propulsion control logic means on one car of said pair jointly responsive to the activation of either directional train line and to predetermined operating factors during movement of said car pair for determining the optimum mode of a first and a second predetermined operating mode of said car pair, c. a selector means on each car coupled to said communication channels and operable for activating a selected one of said directional train lines to establish the corresponding car as the lead car and the remaining car as the trail car for a desired direction of movement, d. a transmitter means on said one car coupled to said communication channels for at times transmitting a control signal to said other car, e. a receiver means on said other car coupled to said communication channels for receiving said control signal when transmitted, f. a switching means controlled by said control logic means for selecting between said first and said second operating modes in accordance with the determined optimum mode, g. said switching means coupled to said transmitter means for actuating the transmission of said control signal when said first operating mode is selected and for interrupting the control signal transmission when said second operating mode is selected, h. said receiver means also coupled to the propulsion means on said other car and responsive to said control signal for selectively actuating said other car propulsion means to a first or a second operating condition as said control signal is transmitted or interrupted, respectively.
 2. said relay coupled to the rectifier output for receiving energy when said control signal is received, d. said relay further coupled for actuating the propulsion control means of the corresponding car to its first and second operating conditions as said relay is energized and deenergized, respectively.
 2. A control system as defined in claim 1 in which said first operating mode comprises the propulsion means of both cars of said pair conditioned to operate under multiple unit control by the operator of the train including said pair of cars and said second operating mode comprises the propulsion means of a single car only conditioned to operate under said operator''s control, the second car propulsion means being in a preset condition.
 2. rectification means for coupling said relay to said channels to respond to said alternating current control signal when transmitted.
 2. rectification means for coupling said relay to said channels to be energized when said alternating current signal is present.
 2. said relay coupled to the rectifier output for receiving energy when said control signal is received, c. said relay further coupled for actuating the propulsion means of said other car to its first and second operating conditions as said relay is energized and deenergized, respectively.
 2. a rectification network for coupling the associated relay to a preselected one of said channels, different for each car, to respond at times to said control signal, b. a directional relay coupled to said channels and responsive to the selection of a lead car by said selector means for coupling said transmitter means to the preselected channel to which the receiver relay on the trail car is coupled by its associated rectification network.
 3. A control system as defined in claim 2 in which, a. said transmitter means further includes an oscilLator for supplying when activated an alternating current control signal having a preselected frequency characteristic, b. said switching means is connected for activating said oscillator only when said first operating mode is selected, c. said receiver means comprises,
 4. A control system as defined in claim 2 in which, a. said transmitter means further includes a source of direct current energy for supplying said control signal, b. said switching means connects said source to said communication channels only when said first operating mode is selected, and c. said receiver means comprises a relay responsive to direct current energy and coupled to said channels and the corresponding propulsion means for shifting said propulsion means between its multiple unit and preset operating conditions as said source is, respectively, connected to or disconnected from said channels.
 5. A control system as defined in claim 1 in which, a. said transmitter means further includes an oscillator for supplying when activated an alternating current control signal having a preselected frequency characteristic, b. said switching means is coupled for at times activating said oscillator in accordance with the selected operating mode for said cars, and c. said receiver means comprises,
 6. A control system as defined in claim 5 in which said combination further includes, a. a receiver means on each car including,
 7. A control system as defined in claim 1 in which, a. said transmitter means includes a direct current energy source and said switching means,
 8. A control system as defined in claim 1 in which, a. said transmitter means includes an oscillator for transmitting, when actuated by said switching means, an alternating current control signal having a preselected frequency characteristic,
 9. A control system as defined in claim 1 in which, a. said transmitter means includes an oscillator for transmitting, when actuated by said switching means, an alternating current control signal having a preselected frequency characteristic, 